Home / 1,387.24-1,912.60-989.35

Finding the Fourth Proportional to 1,387.24, 1,912.60 and 989.35

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Solution

The fourth proportional to 1,387.24, 1,912.60 and 989.35 is: 1,364.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,387.24 : 1,912.60 = 989.35 : x
  2. Step 2: Convert to fraction form
    1,387.24/1,912.60 = 989.35/x
  3. Step 3: Cross multiply
    1,387.24x = 1,912.60 × 989.35
  4. Step 4: Simplify right side
    1,387.24x = 1,892,238.02
  5. Step 5: Solve for x
    x = 1,892,238.02/1,387.24
  6. Step 6: Final answer
    x = 1,364.03

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.